Originally Posted by Team Plutonium
I agree with all of your points, but the drive for more power can never be rationalized. I upgraded from the 535 kit - to the 600 kit, then the 625 kit, and right before I sold the car I was talking to Roman about a 700 kit with a build motor. It was fun, but obviously having enough power is all relative. I grew up in Germany, and when I moved from a 45 HP Renault R5 to a Fiat Uno with 75 HP I felt like Senna driving around town.
And I did go from a 650+ monster to the 400 hp 911, and while I adore the 911 for all what is (it is my dream car after all), I do miss the raw power of the supercharged M3 once in a while.
I think the quest for (always and ridiculous) more power is fun, but expensive, nothing wrong with that, but you have to accept the risks, be it engine related, or accident related. The later is something nobody talks about all that much, but the chance of getting into trouble with 600+ horsepower cars is far greater (well, faster really), then their stock counterparts.
I do know what you mean. I still have the memory of my S4. 2.7L twin turbo V6 with 25 lbs of boost. The enormous swell of midrange torque just nailed you into the seat. There is an absolute level of speed capability that is required, but I feel that a stock M3 (and 991S) is well in that range. Beyond that, it is other subjective qualities that become more important. I also agree with what you said about the risk of really high power. I would be able get going so fast on public roads so quickly without realizing it. Part of the fun of driving is the sensory experience of the feedback you get from a car while pushing it. If you can't safely do this, part of the fun is lost.
In that sense, if your goal is truly just to go fast, then a car like the GTR will suit your needs best. It is an instrument for speed and is purpose built for nothing else other than to go super fast in as safe and controlled manner as can be engineered.